The present invention relates to caps for water bottles and similar containers of various sizes and, more particularly, to an improved upper cap design for simplifying application of the cap onto a bottle neck.
Current designs for five gallon water bottle closures or caps include a seal bead on the under side of the cap and above a locking bead that biases the seal bead down against the crown of the bottle neck to tightly seal the cap around the crown. The locking bead snaps down and around the upper crown of the bottle neck to concentrate the lower load onto the upper side of the crown and onto a smaller surface region, which raises the surface pressure on the cap and thereby improves the seal. Some caps are provided with foam on the under side of the top panel of the cap, because the foam conforms to irregularities in the crown surface and as a result enhances the effectiveness of the seal.
U.S. Pat. No. 3,979,002 of Faulstich discloses a water bottle cap with no seal bead and which is intended to thread onto a bottle neck. The upper region of the cap has an outwardly angled, somewhat conical shape defined at its lower edge by an external bead that fits around an external upper thread located above the crown. U.S. Pat. No. 3,392,860 also of Faulstich discloses a similar cap design. The design of the upper cap region of the present invention improves upon the cap designs shown in these patents.
Various designs for bottle caps are shown in U.S. Pat. Nos. 3,392,862 and 3,840,137 of Faulstich, and 4,884,707 of Crisci, which disclose seal bead designs where the seal bead is located beneath the crown of the bottle neck, which requires the seal bead to be completely pushed down beneath the crown. U.S. Pat. Nos. 4,911,316 of Tackles, 5,121,846 of Adams et al., and 5,232,125 of Adams disclose designs where the seal bead engages the top surface of the crown. With these three later designs, the seal bead is generally aligned with the locking bead and, to some extent, increases the frictional resistance generated when pushing the locking bead down over the crown. All of the foregoing patents provide general background information on the state of the art for cap designs.
Briefly described, the improved closure of the present invention includes a top panel for closing off a container neck opening and a skirt depending from the top panel for covering upper side portions of the container neck. A locking bead extends inwardly from the interior side of the skirt at a location spaced from the top panel. The locking bead is adapted to mount underneath the upper crown upon full mounting of the closure on the container neck. The upper portion of the skirt from the locking bead to the top panel is angled inwardly, to direct at least a portion of the application force radially outwardly to assist the locking bead in clearing the upper crown.
According to an aspect of the invention, the locking bead is positioned radially outwardly of the perimeter bead. The upper skirt portion can take on any of a variety of shapes, but preferably is angled in order to efficiently direct the application force to the locking bead. Preferably, the angled upper portion of the skirt is frustoconical.
According to this aspect of the invention, the upper portion of the skirt directs at least a portion of the application force along a path directly outwardly of the upper crown. This assists in pushing the locking bead down around the upper crown of the container neck. The stiffness of the frustoconical upper cap decreases as the angle from vertical increases. An optimum angle can be determined where sufficient stiffness and radially directed force are both achieved.
According to another aspect of the invention, the top panel includes a raised perimeter bead adjacent the periphery of the top panel for receiving an application force to mount the closure onto the neck.
These and other features, objects, and advantages of the present invention will become apparent from the following description of the best mode for carrying out the invention, when read in conjunction with the accompanying drawings, and the claims, which are all incorporated herein as part of the disclosure of the invention.